UNION

Like structures, union is a collection of data items of different types. The only difference between structure and union is from the view point of storage of their members. All the members of a structure are assigned separate memory locations, but union allows you to view a single storage area in more then one way, i.e all the members of a union the same memory area.

In Computer Programming,an Array,also known as a Vector or List,is one of the simplest data structure.Array holds equally sized data elements, generally of the same data type.In this individual elements are accessed by index(for ex arry[0],arry[2] here 0 and 2 are the index).